While Fools should generally take the opinion of Wall Street with a grain of salt, it's not a bad idea to take a look at particularly stock-shaking analyst upgrades and downgrades -- just in case their reasoning behind the call makes sense.

What: Shares of Walt Disney (DIS -0.45%) gained slightly in pre-market trading Thursday after Jefferies initiated coverage on the entertainment gorilla with a buy rating.

So what: Along with the bullish call, analyst John Janedis planted a price target of $100 on the stock, representing about 19% worth of upside to yesterday's close. So while contrarian traders might be turned off by Disney's price strength over the past year, Janedis' call could reflect a sense on Wall Street that strong operating tailwinds give the stock plenty of room to run.

Now what: Jefferies sees 2014, 2015, and 2016 earnings per share for Disney of $4.27, $4.71, and $5.57, respectively, versus the Wall Street consensus of $4.18, $4.63, and $5.30. "We think Disney is still at the early stages of a multi-year run where all segments will post solid growth," said Janedis. "In our view, the combination of pricing power and resulting margin expansion at the parks, continued success at the film studio with associated flow-through at the consumer segment, what we expect will be at least high single digit EBIT growth at the cable nets (we assume modest upside to current high single digit guidance, though are not modeling it), and sustained return of capital, will drive upside in the stock." When you couple that upbeat outlook with Disney's still-reasonable PEG of 1.2, it's tough to disagree with Jefferies' bullishness.